SOLUTION: cos(2x)=cos^2(x)-sin^2(x)

SOLUTION: cos(2x)=cos^2(x)-sin^2(x)

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Question 1016544: cos(2x)=cos^2(x)-sin^2(x)
Answer by robertb(5830) (Show Source): You can put this solution on YOUR website!
cos2x = cos(x + x) = cosx*cosx - sinx*sinx = cos^2(x) - sin^2(x), by a direct application of cosine of sum of angles.
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